Freeze protector



y 1968 I R. c. SADDISON 3,384,123

FREEZE PROTECTOR Filed May 27, 1966 2 Sheets-Shet 1 To v oMv\2essoRNO'LZLE LIQLHD. SUPPLY ANTI FREEZE 'SOUILCE Ea/ COMPRESSED GAS JB- B ATTOEA/EYS.

y 1968 R. c. SADDISON 3,384,123

FREEZE PROTECTOR Filed May 27, 1966 2 Sheets-Sheet 2 NOZZLE \---T 1/1,"HMEK l l a/c .57 V l ESSQSE F/C. 4

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V INVENTOR E 2055,67 c. 5400/50 H65 z/wwi gwdz ATTOBA/[YS United StatesPatent 3,384,123 FREEZE PROTECTOR Robert C. Saddison, Rte. 1, Sturgis,Mich. 49091 Filed May 27, 1966, Ser. No. 553,445 8 Claims. (Cl. 138-34)This invention relates to a system for preventing a freezable liquidfrom freezing in conduits and, more particularly, relates to a freezeprotecting system for selfservice car wash units, which system willprevent water from becoming frozen in conduits which are exposed tobelowfreezing temperature conditions.

The invention was specifically developed for use in selfservice car washunits and, accordingly, the following description will proceed primarilywith reference thereto. However, it will be understood that theinvention can be used in other environments and that the followingdescription of one particular use of the invention is given forillustrative purposes only and is not of limiting significance.

The conduits that supply water, soap, etc., to self-service car washunits usually are exposed to the ambient air in whole or in part so thatif the ambient air temperature is below freezing and if water isstationary in the conduits, freezing of the water can occur which cancause damage to the conduits and associated fittings and which at leastwill require unthawing of the stoppage. A common way to avoid thisproblem is to continuously flow water through the conduits at a slowrate when freezing conditions are likely to occur. However, thisprocedure Wastes water and, perhaps more importantly, creates unsafeconditions because the water discharged from the conduit can freeze onthe floor of the car wash unit. When the car wash unit is not used forseveral hours, the amount of ice thus formed can be quite substantialand can constitute a significant hazard to the users of the car washunit. In some cases special draining arrangements are provided to removethis water and this increases the cost of the installation appreciably.

Other prior art apparatuses intended for dealing with this problem havedone so by blowing air through the conduit in an attempt to dischargeall of the water therefrom before freezing can occur. However, theseapparatuses do not remove any ice which already may have formed in theconduit. Moreover, often not all of the water is removed from theconduit in this fashion so that the remaining water can collect in lowspots and freeze so that stoppage of the conduit can take place. Also,drops of water can freeze in the nozzle when air is used to blow waterout of the line.

Still other prior art apparatus use electric heating means, such astapes wrapped around the pipes, to prevent freezing. These are notcompletely satisfactory because of increased installation and operationcosts. Also, such installations are bulky and are easily broken. Moreover, it has not been possible to heat the nozzle which is the placewhere freezing is most likely to occur.

Further, since self-service car wash units usually are unattended, afreeze protecting system for use therewith must be capable of automaticoperation in response to the ending of a car washing cycle withoutrequiring intervention by the operator or user of the car wash unit.

Accordingly, it is an object of this invention to provide an improvedsystem for preventing the freezing of a freezable liquid in conduits bywhich system a predetermined amount of an antifreeze liquid is forcedthrough the conduit and also a gas, such as air, is forced through theconduit to remove substantially all of the liquid remaining therein.

It is a further object of this invention to provide an improved system,as aforesaid, in which the operation of 3,384,123 Patented May 21, 1968ice the freeze protecting system is automatically responsive tooperation of the timing control of the car wash unit and will functionautomatically a selectable time after completion of a car washing cyclein order to prevent freezing of the liquid in the conduit.

It is a further object of this invention to provide a freeze protectingsystem, as aforesaid, which does not require any major alteration of thecar washing unit with which it is used so that the freeze protectingsystem can be added to existing car washing units or sold as an optionalaccessory with new car washing units.

A further object of this invention is to provide a freeze protectingsystem, as aforesaid, which is made of relatively inexpensive anddurable components so that it can be manufactured and assembledinexpensively and so that it will operate effectively with a minimum ofmaintenance.

Other objects and advantages of this invention will become apparent topersons acquainted with equipment of this type upon reading thefollowing disclosure and inspecting the accompanying drawings.

In the drawings:

FIGURE 1 is a schematic illustration of a freeze protecting systemaccording to the invention used in conjunction with a car washing unit.

FIGURE 2 is a fragmentary schematic view of a modification of thesystem.

FIGURE 3 is a fragmentary schematic view of a second modification.

FIGURE 4 is a schematic view of yet another modified system according tothe invention.

FIGURE 5 is a schematic view of still another modified system accordingto the invention.

According to the invention, there is provided a system of preventing thefreezing of liquids in conduits through which a freezable liquid isadapted to How. The system includes a source of antifreeze and acompressed gas source, such as a compressed air source, both of whichare connected to the conduit through which the freezable liquid can fiowin order that antifreeze and a pressurized gas can be supplied to theconduit. Suitable control means are provided for alternatively supplyingfreezable liquid to the conduit or connecting the antifreeze source andthe compressed gas source to the conduit whereby when the fiow offreezable liquid is stopped, the antifreeze and compressed gas can thenbe supplied to the conduit in order to remove substantially all of theliquid remaining in the conduit. A small, but sufficient, amount of theantifreeze may remain in the conduit in order to prevent subsequentfreezing of any liquid remaining in the conduit after the compressed gasflow has been terminated.

The invention can be embodied in a variety of modifications, several ofwhich are described herein.

Referring to FIGURE 1, there is shown a suitable source of a liquidunder pressure which is connected by a supply conduit 11 to a furtherconduit 12. Here the liquid source comprises a pump 10, although it willbe understood that the liquid can be supplied under the pressure of acity water supply system or under gravity flow conditions. Forillustrative purposes, the conduit 12 is here indicated as beingconnected to the nozzle (not shown) of a car wash unit. The conduit 12is assumed to be exposed to the ambient air so that the liquid thereincan freeze when the ambient air temperature is below freezing. It willbe understood that the pump 10 can be connected to a source of hot waterand a car washing agent, but these are not shown because they areconventional and form no part of the present invention. The operation ofthe pump is controlled by a suitable timer 13 in a conventional fashion.

The freeze protecting system includes a conduit 14 which is connectedtothe conduit 12. Check valves 16 3 and 17 are provided in the conduits 11and 14 so that fluids can flow from said conduits to the conduit 12, butnot in the reverse direction.

A solenoid valve 18 has an outlet port connected to the conduit 14 sothat flow of fluid into and through said conduit is controlled by saidvalve. The operating coil of the solenoid valve 18 is connected asindicated by the broken line 19 to the timer 13 so that operation ofsaid valve is under the control of the timer. The timer 13 normally isarranged so that the solenoid valve 18 is opened a short time after thepump is turned off, as will be described in greater detail hereinbelow.

The inlet port of the solenoid valve 18 is connected to one end of aconduit 21 which has an orifice of controllable size, such as a needlevalve 22, therein. The needle valve 22 permits fluid to flow through theconduit 21 at a relatively slow controllable rate as described in detailhereinbelow. The other end of the conduit 21 is connected to the lowerside of a tank 23 which is partially filled with a suitable antifreezeliquid, such as an isopropyl alcohol solution. Thus, the antifreeze canflow from the tank 23 through the conduit 21 at a rate controlled by thesetting of the needle valve 22.

One end of branch conduit 26 is connected to the conduit 21 at a pointbetween the inlet port of the solenoid valve 18 and the orifice 22. Thebranch conduit 26 has an upright intermediate portion and its other endis connected to the tank 23 adjacent the upper end thereof. A source ofa pressurized gas, such as an air compressor 27, is connected to thetank 23 so that the upper portion of the tank is filled with gas underpressure. The arrangement is such that when the valve 18 is closed,antifreeze liquid flows through the conduit 21 and orifice 22 into thebranch conduit 26 and rises therein to substantially the same height, asindicated at 23, as the height of the antifreeze liquid in the tank. Ineffect, the antifreeze liquid in the branch conduit 26 forms a measuredcharge which is discharged through the conduits 14 and 12 when thesolenoid valve 18 is opened.

OPERATION While the operation of the apparatus has been indicated above,the same will be described in additional detail in order to assure acomplete understanding of the invention.

When the pump 10 is operating, liquid is supplied to the conduit 12 andthence to the car washing unit under the control of the timer 13. Thevalve 18 is closed at this time and antifreeze liquid flows from thetank 23 through the conduit 21 and orifice 22 into the branch conduit 26and it rises therein to the level indicated at 28.

A selected time after the timer 13 turns off the pump 10 at the end of acar washing cycle, the solenoid valve 18 is opened. The antifreeze inbranch conduit 26 is under the pressure of the compressed gas in thetank 23 and it is forced through the valve 18 and conduit 14, thenceinto conduit 12 and through the nozzle. The antifreeze liquid isimmediately followed by compressed gas from the tank 23 which removessubstantially all of the liquid remaining in the conduits 14 and 12.While some of the liquid may remain in these conduits, there also willremain some antifreeze which will reduce the freezing point of anyliquid remaining in the conduits so that the likelihood that the liquidwill freeze is minimized.

Although the orifice 22 is continuously open, it is so arranged andadjusted that the antifreeze can flow therethrough at a slow rate. Thus,after substantially all of the anti freeze in conduit 26 has flowed outthrough the valve 18, antifreeze flows at a slow rate through theorifice 22 and is picked up by the flowing gas stream and forms anantifreeze mist therein.

After the valve 18 has been open for an appropriate period of time,which usually is only a few seconds, it is then closed by operation ofthe timer 13. The antifreeze liquid can then flow through the orifice 22into 4 the branch conduit 26 at a relatively slow rate until it reachesthe level 28 therein. The apparatus is then ready to repeat the freezeprotecting cycle.

MODIFICATIONS FIGURE 2 illustrates a modification in which the solenoidvalve 18a has three ports and the valve element is movable to connecttwo of the ports to each other at one time. The conduit 21a is connectedto one port of the valve 18a, conduit 26a is connected to a second portand conduit 14a is connected to the third port of the valve. In theclosed position of the valve 181: as illustrated, conduit 21a isconnected to the conduit 26a so that the antifreeze liquid can flow fromthe conduit 21a to the conduit 26a. In the open position of the valve,conduit 26a is connected to the conduit 14a. The operation of thisembodiment is the same as in the previously described embodiment but itwill be noted that in this embodiment the antifreeze supply iscompletely isolated from the conduit 26a during the time that theantifreeze is being supplied to the conduits 14a and 12.

FIGURE 3 illustrates a further modification in which the antifreeze issupplied from a source 31 to an aspirating fitting 32 which is connectedto the conduit 2112. A compressed gas is supplied from the source 33 toa nozzle 34 in the fitting 32. Thus, when the valve 18b is open so thatthe compressed gas can flow into and through the conduit 21b, dropletsof antifreeze are aspirated into the flowing gas stream in the conduit21b to form a mist therein which is then fed to the conduits 14b and 12.

FIGURE 4 illustrates another modification in which the solenoid valve180 is a three-port valve. The accumulator chamber 36 is connected toone port of the valve 180. Conduit 210 is connected to the second portof the valve 180 and conduit 14c is connected to the third port of thevalve. In one position of the valve, conduit 21c is connected to theaccumulator chamber 36 so that a charge of liquid and gas under pressureis stored in the accumulator chamber. In the other position of thevalve, the accumulators chamber 36 is connected to the conduit so thatthe antifreeze and liquid that accumulates in the chamber 36 can flow tothe conduits 14c and 12.

FIGURE 4 also illustrates a modification in which the supply of thewashing liquid is controlled by a valve 37 in line 11, instead ofturning on or turning off a pump as is the case in the embodiment ofFIGURE 1. The valve 37 can be used in any installation where a pumpsupplies liquid to more than one car washing unit or where the liquid issupplied by city water pressure or gravity flow, rather than by a pump.

FIGURE 5 shows still another modification in which a source 41 of gasunder pressure is connected to oneport of a three-way valve 42. A tank43 of antifreeze is connected by a conduit 44 to another port of thevalve 42. A conduit 46 is connected between the third port of the valve42 and the first port of a further three-Way valve 47. A second port ofvalve 47 is connected by a conduit 48 to the upper part of tank 43 andthe third port of valve 47 is connected to the conduit 14.

When the valves 42 and 47 are positioned so that conduit 44 communicateswith conduit 46 and conduit 46 communicates wtih conduit 48, theantifreeze will fill conduit 46 and part of conduit 48. When the valves42 and 47 are shifted, air from tank 41 will flow through valve 42 andforce the antifreeze present in conduit 46 through the valve 47 andthence through the conduits 14 and 12.

All of the embodiments of the invention provide for the supply ofantifreeze and a compressed gas to a conduit in order to removestoppages in the conduit and in order to remove substantially all of theliquid remaining in the conduit. If any liquid remains in the conduitafter the pressurized gas stops flowing therethrough, there will alsoremain some antifreeze which will remain in the liquid to lower itsfreezing point and thus, minimize the likelihood of a further stoppageoccurring.

It will be understood that the freeze protecting system can be disabled,for example, when freezing conditions are not likely to occur, bydisconnecting the control for the solenoid valve of the freezeprotecting system from the timing control of the car wash unit. Also,the time period between the end of a car wash cycle and operation of thefreeze protecting system can be adjusted as needed in view of theambient temperature conditions and the expected frequency of use of thecar wash unit.

While particular preferred embodiments of the invention have beendescribed, the invention contemplates such changes or modifications aslie within the scope of the appended claims.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. A system for preventing the freezing of liquids in conduits,comprising:

first conduit means and supply means for effecting the supply of afreezable liquid to said first conduit means;

a second conduit means connected to said first conduit means;

a source of an antifreeze and a compressed gas source, both of which areconnected for supplying antifreeze and pressurized gas to said secondconduit means;

control means for alternatively connecting (1) said supply means, and(2) said antifreeze source and said compressed gas source, to said firstconduit means.

2. A system according to claim 1, in which said control means includesvalve means for controlling the flow of gas and antifreeze through saidsecond conduit means to said first conduit means, timing means connectedfor operating said supply means and said valve means alternatively sothat compressed gas and antifreeze is supplied to said first conduitmeans a selected time after said supply means terminates supply of thefreezable liquid to the first conduit means.

3. A system according to claim 1, in which said sources of antifreezeand compressed gas comprise a tank partially filled with antifreezeliquid and the remainder of the tank being filled with compressed gas,further conduit means defining a circuit extending between theliquidcontaining portion of the tank and the gas-containing portion ofthe tank, means defining a restricted orifice in said further conduitmeans whereby the liquid in the further conduit means can reachsubstantially the same height therein as the height of the liquid in thetank at a controllable rate, said second conduit means being connectedto said further conduit means at a position between said orifice and thelevel the liquid reaches in the further conduit means.

4. A system according to claim 3, in which said control means includes avalve in said second conduit means at a position spaced from theconnection of the further conduit means to said second conduit means.

5. A system according to claim 3, in which said control means includes avalve connected at the juncture of said further conduit means and saidsecond conduit means, said valve being adapted alternatively to connect(1) the two sections of the further conduit means on opposite sides ofsaid valve, and (2) the upper section of said further conduit means tosaid second conduit.

6. A system according to claim 1, in which said compressed gas source isconnected to said second conduit means by a third conduit, theantifreeze source being connected to said third conduit and there beingan aspirat ing fitting means at the position where the antifreeze sourceis connected to said third conduit so that flow of compressed gasthrough said third conduit will aspirate antifreeze into the flowing gasstream so that it forms a mist therein.

7. A system according to claim 4, in which the valve has a first portconnected to the further conduit means, a second port connected to anaccumulator and a third port connected to the second conduit, said valvebeing movable between a first position in which said first and secondports are connected and a second position in which the second and thirdports are connected.

8. A system according to claim 2, in which said valve means comprises apair of valves, one valve having first port connected to a source ofcompressed gas, a second port connected to a supply of antifreeze and athird port, the other valve having a first port connected to the thirdport of said one valve, a second'port connected to the anti-freezesupply and a third port connected to said second conduit, means formoving said valves simultaneously between first positions in which thefirst and second ports of each valve are connected to each other andsecond positions in which the first and third ports of each valve areconnected to each other.

References Cited UNITED STATES PATENTS 2,172,882 9/1939 Watkins 138-34 X2,229,498 1/1941 Farmer 138--34 X 3,140,720 7/ 1964 Griswold 13759LAVERNE D. GEIGER, Primary Examiner.

C. L. HOUCK, Assistant Examiner.

1. A SYSTEM FOR PREVENTING THE FREEZING OF LIQUID IN CONDUITS,COMPRISING: FIRST CONDUIT MEANS AND SUPPLY MEANS FOR EFFECTING THESUPPLY OF A FREEZABLE LIQUID TO SAID FIRST CONDUIT MEANS; A SECONDCONDUIT MEANS CONNECTED TO SAID FIRST CONDUIT MEANS; A SOURCE OF ANANTIFREEZE AND A COMPRESSED GAS SOURCE, BOTH OF WHICH ARE CONNECTED FORSUPPLYING ANTIFREEZE AND PRESSURIZED GAS TO SAID SECOND CONDUIT MEANS;CONTROL MEANS FOR ALTERNATIVELY CONNECTING (1) SAID SUPPLY MEANS, AND(2) SAID ANTIFREEZE SOURCE AND SAID COMPRESSED GAS SOURCE, TO SAID FIRSTCONDUIT MEANS.